Negative element for primary batteries.



PATENTED MAY 5, 1908.

U. B. SGHOENMEHL.

NEGATIVE ELEMENT FOR PRIMARY BATTERIES.

' APPLICATION FILED JUNE 2,1905.

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51400441331 (Ikaries Bfldwenm @751 nnrrnn snares PATEWJ CHAR-LES B.SUHQENMEHL, OF WATERBURY, (IONNEOTICUYE.

NEGATIVE ELEMENT FOR PRIEEEZARY EATTEP-Jffild.

Specification of Letters Patent.

Patentediliay 5, 1-908.

Application filed June 2, 1905. Serial No. 263,379.

vented certain new and. useful Improvements in Ne ative Elements forPrimary Batteries, of which the following is a specification.

My invention relates to negative elements or electrodes for electricbatteries, composed of an oxid of metal, as for instance,-copper or anysimilar and suitable oxid.

The object of my invention is to produce a superior oXid electrode ofuniform conductivity and porosity, which will not readily become.oxidized, and especially one which will operate to its fullest capacityat the beginnin of the operation of the battery.

()xlr electrodes of the above class are manufactured in several forms,the two more po )ular styles being known as lates and cylinders but forconvenience of escription l have shown a compressed element of thecylindrical type, upon the accompanying drawing forming a part of thisspecification. It will be obvious however that the particular shape orstyle of the element is not material since any form-of an oxidagglomerate may be treated with beneficial results in accordance with myinvention.

Figure 1, of the drawing shows a side elevation of a cylindrical form ofoxid of copper element, adapted for use in one of my improved forms ofbatteries, and treated in accordance with my present invention. Fi 2, ofthis drawing shows a central vertica cross-section of the cylinder shownin Fig. 1, and illustrating in an exaggerated manner the metallizedsurface.

Referring in detail to the reference characters u on the drawings (1indicates the cylinder the su porting rod therefor and e the metalcovered surface. i

It is the practice in the state of the art to preliminarily reduce thesurface of copper oxid electrodes, which I find produces veryunsatisfactory results as to conductivity and porosity as in theoperation a very large ercentage oxidize thereby losing their conuctivity; and, as the liability to over-reduce is great, theover-reduced electrodes vary greatly in their porosity. The above rela--tive to porosityis equally true when electrodes are subjected to acoating of metal by electro-deposition.- 5

I find that all of the aboveinentioned s ficultiesare obviated by firstmetallizingthc mass of oxid in any suitable way, as by-reduction orelectrolysis, then re-oxidizin said inetallized mass in any suitableway. for instance, by heat or electrolysis, until the compressed oxid'electrodes become suil ciently and uniformly porous. I then treat thisuniformly porous masswith a coating of pure inetalof the oxidin afinelydivided state 1n an suitable way; as for instance, b I brushing onorrubbing on the compresse" agglomerated, metallized and re-oxidise massof oxid. Saidelectiodes being eitcesdingly porous, the finely powderedor divided metal adheres very tenaciously to the electrode and rendersthe compressed mass of oxid more conductive than if the mass were copperoxid with its surface coated with a film of other material. I do notwish'to be understood as confining myself strictly to the abovedescription of making oxid elec trodes as I find satisfacto results can.be. obtained by dispensing wit the afore mentioned method ofmetallizing and. re-oxidizthe oxid mass, by taking a mass of suit- I inalile oxid of the desired shape or form and coating the surface of saidshape or form with finely divided metal bf said o'xid as already hereindescribed.

I find that by my method of coating oxid electrodes with metallic powderof the oxid of the electrode in a finely divided state they do notoxidize as readily as a reduced electrode, and consequently, are moredesirable, inasmuch as they are rendered uniformly conductive. The oxidecan be obtained" in any suitable way; as for instance if oxid of copperis preferred I can make the same by precipitatmg pure metallic copper,from so ution of copper, then washing and drying said precipitate,thereby producir'n a finely divided conductive red copper powder inmetallic form, which is then subjected to sufiicient heat to thoroughlyoxidize the same, which roduccs a pure finely dividedblack oxid o 00 perof superior quality; and I also find that by treating a mass of blackoxid of copper made in the above manner with a coatmg of pureprecipitated metallic cop er I obtain superior results although it is 0vious that any other suitable method shay be used to obtain the desiredform of comminution or either the oxid br metallic powders. I

swam;

3. An agglomerated mass of black oXid of copper hamng lbs surfacemetalhzed mad 0X1- dlzed, and. sand surface coated 'wlth-imely 3311s QEumy invention, and desire'to secure by Lgtters 5 ca comm-2d with. finelySigned sbt Brid e or'b in the county of Faire'a aha same metal as COI1-field and State 0? onnect-icut this 25th day I I t of May A. 1)., 1905.

wnlpressed ()Xid of copper battery I CHARLES B. SCHOENMEHL, element.sempz'ising an aggiomerated mass, Witnesses:

ha g iis slui'zme coated with finely divided 0. M. NEWMAN, 239.;

Liclass 01f memilic copper. 1 RUTH RAYMOND.

91 oxid. bsJttery aledfirided particles of metallic copper. 1:

